Ahmed, who fled his native Pakistan in 2010, could be a late call-up into Australia's squad before the first Test next month if his application for Australian citizenship is fast-tracked. Legislation is currently before the Australian parliament that would allow the 31-year-old to join a 16-man Australia squad that currently only has one specialist slow bowler in Nathan Lyon.

"I think for him the whole story of his is a very courageous one," Warne told BBC Radio 5 Live. "He's come to Australia for a better life. What he has done is an interesting story."

He added: "I wish him all the best and I really hope all the documentation goes through because I think he could be a real surprise element for Australia.

"He's got that surprise element and he doesn't get flustered about anything. I think he could be very good for Australia."

Warne believes Ahmed is already a better option than the 22-capped Lyon, despite the leg-spinner having played just three first-class matches since his arrival Down Under.

Ahmed took 16 wickets in that time, after making his debut in February for Victoria - the same state where Warne began a career that brought him 708 Test scalps. Warne has therefore been a close observer to Ahmed's journey, which he says has put him "through hell".

"He's got a mature head on his shoulders. He's been through hell basically; he's been through a tough time," he said. "He has been a net bowler for the Victorian team and just bowled and bowled in the nets. He's an excellent bowler. On debut he got five-for. He can really bowl. His story is courageous and heroic actually."

Warne backed Australia's current attack to cause England problems during the five-Test series, which begins at Trent Bridge on July 10, but believes Ahmed's inclusion could provide the final piece in ensuring his country claim back the Ashes urn.

"The quick bowling will be good but the spin is lacking. Any time you can get a good leg-spinner in it's good," he said. "I think if anyone under-estimates Australia in the Ashes they do at their own peril because I think they have the side there that could surprise England."